Manufacture of peat-fiber pulp.



UNITED STATES PATENT OFFICE.

AUGUSTE KALMANN, OF RABENSTEIN, AUSTRIA-HUN GARY.

MANUFACTURE OF FEAT-FIBER PULP.

SPECIFICATION forming part of Letters Patent No. 698,118, dated April 22, 1902. Application filed August I7. 1901; Serial No. 72,872. (No specimens.)

use in the production of paper, millboard,

and the like.

The process is carried out in two stagesfirst, the washing and pretreatment of the fibrous material, and, second, the succeeding I5 preparation of the fibrous material for obtaining pulp. The first treatment (washing and cleansing of the fibrous material) is effected in known apparatus and by known means, so that it is thereby freed from all impurities and foreign matters-such as sand,

stones, wood, and the like-and the fibers are roughly opened out and separated.

The apparatus 1, preferably made use of for carrying through this process, consists of a 5 basin of wood, masonry, or beton, provided w1tE two sets of rollers having rough iron teeth on their surface. The rollers rotate in engagement with a bed-plate, also provided with corresponding iron teeth, so that the teeth of the rollers mesh with those of the bed,- plate. By these means the fibrous material is divided under pressure, but without being cut. The rollers are vertically adjustable in order to allow variation of pressure in propor- 3 5 tion tothe:desired effect. Between the toothed rollers there are arranged two drums for washing the material. These drums are also capable of a vertical adjustment. The raw material to be acted upon is introduced into the basin at one end of same and removed at the other end by means of an elevator into depositing-troughs after washing and cleansing has been completed. Above the bottom of this apparatus there is disposed a perforated metal sheet having a recess below each of the two drums for receiving the deposited impurities. Purging-cocks allow evacuation of the deposits at the lowest points of the re cesses. At the sides of the apparatus are tubes so for the supply of sufficient water for washing purposes. As soon as the water drawn off is clear the elevator is put into operation and.

the basin emptied, whereupon the same process may recommence.

' An apparatus as above described may be built up with any number of sets of rollers and bed-plates, so as to suitevery extent of production. quantities of peat-in shortest time and to separate and cleanse the fibrous materialin a thorough manner, as by the broad teeth of the rollers the material is not only disintegrated and the knots opened, but the water is cou-' tinuously maintained in movement, in consequence of the paddle-like shape of the teeth. Thus the fibers are maintained finely sus- It allows to treat the largest.

pended in the water and cannot act as a filter, I

as is ordinarily the case, whereby the impurities are retained, By this disintegration the specific lighter parts of the material-viz. the fiber'sswimming above are separated from the specific heavier parts, (impu rities,) which are allowed to fall upon the inclined perforated sheet metal and therefrom to the bottom of the basin. The washing-drums have for their purpose to receive the finely-divided particles of sand and wood and to separate the same. By this treatment the peat fiber, free of all impurities, is much more capable of ab sorbing water. The cells of the fiber when settlin g down in the troughs is impregnated with water, and thereby gets the natural form and size it had when still in living state. The cleansed and opened material thus produced is then subjected to the'second treatment, in which it is completely opened. For this treatment the material is introduced'into an apparatus in which the material is subjected to frequent intermittent compressions or squeezes of only short duration, whereby the cells are eompletelyopened. This treatment is continued until the material takes the nature of half-pulp. The half-pulp is then removed from the apparatus and allowed to settle, after which it is returned to the apparatus and again subjected to the compressing or squeezing and disintegrating action until the material possesses the properties of pulp fit'for utilization in the manufacture of paper or millboard in the manner and by the means well known. It will be found advantageous to conduct the Whole of the operation in the cold and that the resulting pulp is of excellent quality. For carrying through this plate.

last treatment of the material I preferably use a stuff-engine with a special bed-plate and cylinder and containing a sieve forming a false bottom through its whole length up to the cylinder for the purpose of allowing a repeated thorough washing of the fiber when being ground. In order to allow as completely as possible entering of the water into the cell, and thereby creeping of the latter, the whole engine is covered with strong sheet metal and hermetically closed and so rigidly built up that it may resist a pressure of four atmospheres. The use of air-pressure allows a more quick and subtile treatment. The cylinder carries a suitable nu mberof rounded wellpolishcd knives of steel of sufficient strength, which mesh into a considerably smaller 11 umber of teeth of similar shape as the knives-- that is to say, rounded-not cutting but squeezingavhich teeth are disposed on the bedlhe cylinder may be adjusted in verlical direction and is of considerable weight. The apparatus works as follows: The vat after being supplied with the material obtained by the first treatment and with sufficient water is hermetically closed, the cylinder is lowered so far as to but slightly touch the bedplate in passing, and then the apparatus is started. \Vhen the material is in uniform movement, the cylinder carrying the knives is gradually lowered, so as to more and more engage the bed-plate. Only after about one hours work air-pressure is increased up to two and one-half to three atmospheres, and this pressure is maintained until the material is completely ground. In consequence of the special shape of the knives of the cylinder and of the teeth of the bed-plate onlya squeezing and opening of the cell entirely filled with water is effected, whereby the same gets an indented shape, which allows an intimate felting of the fibers when upon the paper 'mill, and thus secures durability and uniformity of the paper produced. By the repeaied squeezing in the last-described apparatus the fiber treated becomes very supple,

as all the still-adhering foreign matters and impurities are ground and quickly separated from the fiber by the rotation of the feedingserew and are deposited into the sand-boxes after having passed the sieve. This suppleness is obtained by the pure mechanical action of the cylinder provided with rounded knives and by no chemical process.

Having now particularly described and ascertained the nature of my invention and in what manner the same is to be performed, I declare that what I claim is- 1. A process for the manufacture by mechanical agencies of peat-fiber pulp foruse in the production of paper, millboard and the like consisting in washing and opening the raw material, in subjecting it to intermittent compressions removing it from the apparatus and allowing it to settle and in again subjecting it to intermittent compressions, substantially as described.

2. A process for the manufacture by mechanical agencies of peatfiber pulp, for use in the production of paper, millboard and the like, consisting in washing and opening the raw material, in subjecting it to intermittent compressions, removing it from the apparatus and allowing it to settle and in again subjecting it to intermittent compressions, under high air-pressure, substantially as described.

In witness whereof I have hereunto signed my name, this 2d day of August, 1901, in the presence of two subscribing witnesses.

AUGUSTE KALMANN. lVitnesses:

JOI-IANN FLoTH, ALVESTO S. Houun. 

